In many systems, it is well recognized that overtravel stops are commonly utilized as an important component. For instance, in aircraft actuation systems, overtravel stops which are effective and reliable must be provided in order to assure proper functioning of critical components. Moreover, it is important to provide lightweight, bi-directional, repeatable and non-jamming overtravel stops for such applications.
An additional necessary feature of overtravel stops utilized in aircraft actuation systems includes accommodating numerous revolutions of rotation between each end stop. Frequently, a torque limiting device is also needed as a part of the same system. Accordingly, it would be highly desirable to provide a single device accomplishing both functions with fewer parts.
Among devices disclosed in the prior art are those of Rowley et al, U.S. Pat. No. 2,837,925, and Pollock, U.S. Pat. No. 2,902,876. These devices generally relate to differential type overtravel limit stops. However, neither Rowley et al nor Pollock disclose or suggest the use of any type of torque limiter therewith.
Other devices which have been proposed include those in Hoover, U.S. Pat. No. 3,221,118 and Jelinek et al, U.S. Pat. No. 4,479,397. The devices disclosed therein include overtravel screws with brakes. However, neither Hoover nor Jelinek et al disclose or suggest a torque limiter in combination with an overtravel stop.
The present invention is directed to overcoming the above-stated problems and accomplishing the stated objects in an effective, reliable and efficient manner.